In the existing technology, when a person passes through a device such as a gate or an entrance guard, identity authentication needs to be performed on the person. However, a user's initiative participation is needed to achieve identity authentication in the existing manners of identity authentication. For example, both fingerprint authentication and iris authentication need close contact with the user. Although face authentication is a non-contact manner, close-range acquisition needs to be performed on the user. On the other hand, the existing manners of identity authentication also have certain requirements on the angle, light, and definition of the acquired image of a body part of the user, and has strong perceptibility and a relatively strict authentication condition.
The above information disclosed in the background is only for enhancing an understanding of the background of the present disclosure. Therefore, it may contain information that does not constitute the existing technology known to those skilled in the art.